Diskutil format disk to ExFAT


List all disks

diskutil list

The disk4 and disk5 are linked

/dev/disk0 (internal, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *1.0 TB     disk0
   1:                        EFI EFI                     209.7 MB   disk0s1
   2:                  Apple_HFS Backup                  465.6 GB   disk0s2
   3:                  Apple_HFS Data                    533.6 GB   disk0s3

/dev/disk1 (external, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *256.1 GB   disk1
   1:                        EFI EFI                     209.7 MB   disk1s1
   2:                 Apple_APFS Container disk3         255.9 GB   disk1s2

/dev/disk2 (external, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *128.0 GB   disk2
   1:                        EFI EFI                     209.7 MB   disk2s1
   2:       Microsoft Basic Data OldSSD                  127.8 GB   disk2s2

/dev/disk3 (synthesized):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      APFS Container Scheme -                      +255.9 GB   disk3
                                 Physical Store disk1s2
   1:                APFS Volume OSX                     43.2 GB    disk3s1
   2:                APFS Volume Preboot                 19.3 MB    disk3s2
   3:                APFS Volume Recovery                509.8 MB   disk3s3
   4:                APFS Volume VM                      4.3 GB     disk3s4

/dev/disk4 (external, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *240.1 GB   disk4
   1:                        EFI EFI                     209.7 MB   disk4s1
   2:                 Apple_APFS Container disk5         239.8 GB   disk4s2

/dev/disk5 (synthesized):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      APFS Container Scheme -                      +239.8 GB   disk5
                                 Physical Store disk4s2
   1:                APFS Volume BadSSD                  852.0 KB   disk5s1
   2:                APFS Volume Preboot                 19.3 MB    disk5s2
   3:                APFS Volume Recovery                509.8 MB   disk5s3
   4:                APFS Volume VM                      4.3 GB     disk5s4

Delete APFS container in disk5

diskutil apfs deleteContainer /dev/disk5

List all disk again to see the result

diskutil list

The disk5 deleted and updated disk4 status to Untitled like

/dev/disk0 (internal, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *1.0 TB     disk0
   1:                        EFI EFI                     209.7 MB   disk0s1
   2:                  Apple_HFS Backup                  465.6 GB   disk0s2
   3:                  Apple_HFS Data                    533.6 GB   disk0s3

/dev/disk1 (external, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *256.1 GB   disk1
   1:                        EFI EFI                     209.7 MB   disk1s1
   2:                 Apple_APFS Container disk3         255.9 GB   disk1s2

/dev/disk2 (external, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *128.0 GB   disk2
   1:                        EFI EFI                     209.7 MB   disk2s1
   2:       Microsoft Basic Data OldSSD                  127.8 GB   disk2s2

/dev/disk3 (synthesized):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      APFS Container Scheme -                      +255.9 GB   disk3
                                 Physical Store disk1s2
   1:                APFS Volume OSX                     43.2 GB    disk3s1
   2:                APFS Volume Preboot                 19.3 MB    disk3s2
   3:                APFS Volume Recovery                509.8 MB   disk3s3
   4:                APFS Volume VM                      4.3 GB     disk3s4

/dev/disk4 (external, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *240.1 GB   disk4
   1:                        EFI EFI                     209.7 MB   disk4s1
   2:                  Apple_HFS Untitled                239.7 GB   disk4s2

Now, Format the disk4 Untitled to ExFat and named SSD20180321 or usign the Disk Utility app

diskutil eraseDisk EXFAT SSD20180321 /dev/disk4

Reference